Following a backlash on social media to the comments the Police Federation for Northern Ireland - the body that represents rank and file officers - described the Chief Constable's "outburst" as "offensive" and a "great insult."

Mr Hamilton made the comments on Twitter in response to a tweet from an officer who said: "police expected to do more roles than ever anticipated by Sir Robert (Peel)! Social worker, paramedic, child minder etc"

The Chief Constable responded: "I know - more complex & challenging but we are here to serve so let's get on with it rather than wallowing in self pity!"

The officer Tweeted back: "Far from self pity. If I wanted to do their job I would have applied. Just keep taking their responsibilities & no one says no."

Mr Hamilton then replied: "well you're allowed to leave & seek another job - nobody is asking you to stay. Dry your eyes, do the job or move on!"

Police Federation chairman Mark Lindsay demanded an apology.

"Mr Hamilton has got this badly wrong. To say to Officers to ‘dry your eye, do the job or move on’ amounts to great insult and a stunning misjudgement. He should apologise immediately for this outburst, withdraw the offensive comments and remove the tweet from his account," he said.

In a video message posted on Twitter on Sunday afternoon Mr Hamilton apologised.

He said in a statement: “Last night’s frank Twitter conversation was about what policing does.

"It is important to have meaningful exchanges on social media without lapsing into ‘management speak’.

"However, such issues are not always best addressed in the 140 characters of a tweet. I have clearly caused offence by my response and for this I apologise.

"The real debate needs to be about the role of the police and, where that starts and finishes, and the impact it has on officers, staff and their families.

"I have already spoken to the Chair of the Police Federation and will be happy to discuss these issues over the coming days with the respective Staff Associations.

"Policing is a complex and challenging profession. I am hugely proud of the work my officers and staff do every day in serving the public and I want to support and encourage these great people. My message last night would not have conveyed that support and for that I am sorry.”

Ulster Unionist MLA Doug Beattie MC was among whose who called on the Chief Constable to reflect on the words he used in the tweet.

He said: “I have incredible respect for our police force and all those who serve in it, and I have had first-hand experience of seeing just what they have to deal with and the mental effects this can have on individual officers. Therefore I am incredibly disappointed by the PSNI Chief Constable’s response on Twitter to genuine concerns, stating that officers should get on with it, stop wallowing in self-pity, dry your eyes or leave.

“This attitude of ‘we will make do regardless’ has seen the PSNI budget cut again by 2%. It has seen its policing levels - which were set by the Patten report at 7,500 - remain 600 officers short, not counting those on long term sick leave. It has allowed our Justice Minister to promise the delivery of more Neighbourhood policing without increasing police resources, which in turn could lead to paramilitaries policing our streets. But worse of all, it has led our proud police service morale to plummet in some areas.

“I do not envy the job of the PSNI Chief Constable. He has a difficult task on his hands with an ever decreasing budget and political masters who are slow to make decisions. But there comes a time when he must say enough is enough and stand up for his officers when they raise genuine concerns.

"I hope he reflects on his poorly formulated tweet, deletes it and makes it known that he is not a ‘carry on regardless’ Chief Constable but a man of integrity who will not allow our service to degrade to little more than a political football. The brave men and women of the PSNI deserve better than that.”